ntlm_auth — tool to allow external access to Winbind's NTLM authentication function
ntlm_auth [-d debuglevel] [-l logdir] [-s <smb config file>]
This tool is part of the samba(7) suite.
ntlm_auth is a helper utility that authenticates
users using NT/LM authentication. It returns 0 if the users is authenticated
successfully and 1 if access was denied. ntlm_auth uses winbind to access
the user and authentication data for a domain. This utility
is only intended to be used by other programs (currently
Squid
and mod_ntlm_winbind)
The winbindd(8) daemon must be operational for many of these commands to function.
Some of these commands also require access to the directory
winbindd_privileged in
$LOCKDIR. This should be done either by running
this command as root or providing group access
to the winbindd_privileged directory. For
security reasons, this directory should not be world-accessable.
Operate as a stdio-based helper. Valid helper protocols are:
Server-side helper for use with Squid 2.4's basic (plaintext) authentication.
Server-side helper for use with Squid 2.5's basic (plaintext) authentication.
Server-side helper for use with Squid 2.5's NTLMSSP authentication.
Requires access to the directory
winbindd_privileged in
$LOCKDIR. The protocol used is
described here: http://devel.squid-cache.org/ntlm/squid_helper_protocol.html.
This protocol has been extended to allow the
NTLMSSP Negotiate packet to be included as an argument
to the YR command. (Thus avoiding
loss of information in the protocol exchange).
Client-side helper for use with arbitrary external programs that may wish to use Samba's NTLMSSP authentication knowledge.
This helper is a client, and as such may be run by any
user. The protocol used is
effectively the reverse of the previous protocol. A
YR command (without any arguments)
starts the authentication exchange.
Server-side helper that implements GSS-SPNEGO. This
uses a protocol that is almost the same as
squid-2.5-ntlmssp, but has some
subtle differences that are undocumented outside the
source at this stage.
Requires access to the directory
winbindd_privileged in
$LOCKDIR.
Client-side helper that implements GSS-SPNEGO. This also uses a protocol similar to the above helpers, but is currently undocumented.
Server-side helper protocol, intended for use by a RADIUS server or the 'winbind' plugin for pppd, for the provision of MSCHAP and MSCHAPv2 authentication.
This protocol consists of lines in the form:
Parameter: value and Parameter::
Base64-encode value. The presence of a single
period . indicates that one side has
finished supplying data to the other. (Which in turn
could cause the helper to authenticate the
user).
Currently implemented parameters from the external program to the helper are:
The username, expected to be in Samba's unix charset.
The user's domain, expected to be in Samba's unix charset.
The fully qualified username, expected to be in Samba's unix charset and qualified with the winbind separator.
The 8 byte LANMAN Challenge value,
generated randomly by the server, or (in cases such as
MSCHAPv2) generated in some way by both the server and
the client.
The 24 byte LANMAN Response value,
calculated from the user's password and the supplied
LANMAN Challenge. Typically, this
is provided over the network by a client wishing to authenticate.
The >= 24 byte NT Response
calculated from the user's password and the supplied
LANMAN Challenge. Typically, this is
provided over the network by a client wishing to authenticate.
The user's password. This would be provided by a network client, if the helper is being used in a legacy situation that exposes plaintext passwords in this way.
Upon successful authenticaiton, return the user session key associated with the login.
Upon successful authenticaiton, return the LANMAN session key associated with the login.
Specify username of user to authenticate
Specify domain of user to authenticate
Specify the workstation the user authenticated from
NTLM challenge (in HEXADECIMAL)
LM Response to the challenge (in HEXADECIMAL)
NT or NTLMv2 Response to the challenge (in HEXADECIMAL)
User's plaintext password
If not specified on the command line, this is prompted for when required.
For the NTLMSSP based server roles, this parameter specifies the expected password, allowing testing without winbindd operational.
Retrieve LM session key
Request NT key
Perform Diagnostics on the authentication
chain. Uses the password from --password
or prompts for one.
Require that a user be a member of specified group (either name or SID) for authentication to succeed.
level is an integer
from 0 to 10. The default value if this parameter is
not specified is 0.
The higher this value, the more detail will be logged to the log files about the activities of the server. At level 0, only critical errors and serious warnings will be logged. Level 1 is a reasonable level for day-to-day running - it generates a small amount of information about operations carried out.
Levels above 1 will generate considerable amounts of log data, and should only be used when investigating a problem. Levels above 3 are designed for use only by developers and generate HUGE amounts of log data, most of which is extremely cryptic.
Note that specifying this parameter here will
override the parameter
in the smb.conf file.
Prints the program version number.
The file specified contains the
configuration details required by the server. The
information in this file includes server-specific
information such as what printcap file to use, as well
as descriptions of all the services that the server is
to provide. See smb.conf for more information.
The default configuration file name is determined at
compile time.
Base directory name for log/debug files. The extension
".progname" will be appended (e.g. log.smbclient,
log.smbd, etc...). The log file is never removed by the client.
Print a summary of command line options.
To setup ntlm_auth for use by squid 2.5, with both basic and
NTLMSSP authentication, the following
should be placed in the squid.conf file.
auth_param ntlm program ntlm_auth --helper-protocol=squid-2.5-ntlmssp auth_param basic program ntlm_auth --helper-protocol=squid-2.5-basic auth_param basic children 5 auth_param basic realm Squid proxy-caching web server auth_param basic credentialsttl 2 hours
This example assumes that ntlm_auth has been installed into your
path, and that the group permissions on
winbindd_privileged are as described above.
To setup ntlm_auth for use by squid 2.5 with group limitation in addition to the above
example, the following should be added to the squid.conf file.
auth_param ntlm program ntlm_auth --helper-protocol=squid-2.5-ntlmssp --require-membership-of='WORKGROUP\Domain Users' auth_param basic program ntlm_auth --helper-protocol=squid-2.5-basic --require-membership-of='WORKGROUP\Domain Users'
If you're experiencing problems with authenticating Internet Explorer running under MS Windows 9X or Millennium Edition against ntlm_auth's NTLMSSP authentication helper (--helper-protocol=squid-2.5-ntlmssp), then please read the Microsoft Knowledge Base article #239869 and follow instructions described there.